|Publication number||US5952615 A|
|Application number||US 08/713,700|
|Publication date||Sep 14, 1999|
|Filing date||Sep 13, 1996|
|Priority date||Sep 15, 1995|
|Also published as||DE69616927D1, EP0763831A1, EP0763831B1, US6566605|
|Publication number||08713700, 713700, US 5952615 A, US 5952615A, US-A-5952615, US5952615 A, US5952615A|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (11), Referenced by (84), Classifications (9), Legal Events (6) |
|External Links: USPTO, USPTO Assignment, Espacenet|
Multiple pair cable with individually shielded pairs that is easy to connect
US 5952615 A
A multiple pair cable with individually shielded pairs and that is easy to connect has a circular cross-section and includes a plurality of individually insulated conductor pairs and an electrical shield around each pair. The electrical shields of the various pairs include a central rod with radial fins separating the pairs from each other and partially shielding each pair and a peripheral shield around the rod and all of the pairs between the fins and completing the shielding of each pair.
There is claimed:
1. A cable having a circular cross-section and including a plurality of individually insulated conductor pairs, said cable comprising:
an electrical shield surrounding each of said conductor pairs;
said electrical shield including a central rod with radial fins separating said conductor pairs from each other for partially shielding each of said conductor pairs, and a peripheral shield surrounding said rod and all of said conductor pairs between said fins for completing the shielding of each of said conductor pairs,
wherein said rod comprises an insulative material member of constant cross-section with an exterior metallization that is continuous from one fin to the next.
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention concerns cables comprising multiple pairs of individually insulated electrical conductors for transmitting high-frequency signals with low crosstalk between the pairs, for example computer cables. It concerns in particular a multiple pair cable with individually shielded pairs that is easy to connect.
2. Description of the Prior Art
Crosstalk is a key parameter in this type of cable and crosstalk can be considerably reduced by individually shielding the pairs of the cable.
The most common solution to the problem of shielding each pair is to wrap a metal or metallized tape helically around each pair before assembling the individually shielded pairs into a common protective sheath. Tape wrapping each pair is a lengthy operation, and is necessarily carried out as an additional stage on each pair already made up in order to obtain satisfactory high-frequency transmission characteristics. Tape wrapping during the construction of the pairs is not suitable since the pitch of the tape wrap is then the same as that of the conductors in each pair concerned and the regularity of the pitch required for compatibility with transmission at high bit rates cannot be guaranteed.
To connect the cable the individual shields of the pairs must be removed to obtain access to the conductors, which makes connection on site a lengthy and difficult operation.
Document GB-A-1 546 609 describes a computer cable with a plurality of individually shielded pairs. This cable is a flat cable with the pairs side-by-side. The pairs are shielded by two tapes which cover all of the pairs extending between them and are joined together on each side of each pair. Each shielding tape comprises a strip of metal, for example aluminum, coated on at least one side with a thermoplastics material and preferably on the other side with a synthetic polyester resin. The sides covered with the thermoplastics material are placed face-to-face in order to bond them by application of heat and thereby connect the two shielding tapes.
A tearing line is provided along each area of joining of the two tapes between the pairs, either on both tapes or preferably on one tape only. Such tearing lines facilitate access to the conductors of the pairs for connecting the cable.
A drawback of this cable is the result of its flat structure, which makes the cable relatively wide and flexible in one direction only so that it tends to twist during installation. This is a problem in particular in the case of a flat cable comprising four pairs, like the type of cable most frequently used in computer networks, as the cable is then very wide. It is necessary to untwist it during installation and this makes it very vulnerable to traction.
Document U.S. Pat. No. 3,819,443 describes a shielding member comprising laminated strips of metal and plastics material that are cut, bent and assembled together to define radial branches on said member. It also describes a cable including a set of conductors arranged in pairs, said shielding member and an insulative outer sheath around the set of conductors. In this cable the shielding member with the radial branches compartmentalizes the interior of the cable. The various pairs of the cable are therefore separated from each other, but each is only partially shielded, which is not so effective as shielding around each pair and is not always satisfactory.
An object of the present invention is to provide a multiple pair cable with individually shielded pairs that is easy to connect and has a circular cross-section that does not have the drawbacks of the previously described flat cable with individually shielded pairs.
SUMMARY OF THE INVENTION
The invention consists in a multiple pair cable with individually shielded pairs and that is easy to connect, having a circular cross-section and including a plurality of individually insulated conductor pairs and an electrical shield around each pair, wherein the electrical shields of the various pairs comprise a central rod with radial fins separating the pairs from each other and partially shielding each pair and a peripheral shield around the rod and all of the pairs between the fins and completing the shielding of each pair.
The above cable advantageously has at least one of the following additional features:
the rod includes at least one metal tape inside the fins and covered with a common insulative covering,
the rod comprises an insulative material member of constant cross-section with an exterior metallization that is continuous from one fin to the next,
the rod is made from a semiconductor polymer material and has a constant cross-section,
the rod is twisted into a spiral.
The features and advantages of the invention will emerge from the following description of the embodiments shown in the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a cable of the present invention.
FIG. 2 is a cross-sectional view of a variant of the same cable.
FIG. 3 is a cross-sectional view of another variant of the same cable.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The cable shown in FIGS. 1 and 2 has a circular cross-section. It comprises four pairs 1 through 4 of electrical conductors, the pairs being individually shielded, and a protective outer sheath 5 around the set of shielded pairs.
The conductors of the pairs are identical. Each has a conductive core 6 surrounded by insulation 7. The two electrical conductors of each pair are twisted together. The cable can obviously include a different number of pairs, although the cables most widely used in computer networks have four pairs.
In FIG. 1, the pairs are individually shielded by a rod 10 with radial fins 11 which separate the pairs and partially shield each pair and by a peripheral shield 13 surrounding the rod and the set of pairs in place therein and completing the shielding of each pair.
For this cable with four pairs the rod 10 with fins 11 is cruciform in shape and defines four V-shape compartments 14 each receiving one of the four pairs. It comprises two metal tapes 15 in a cruciform arrangement covered with insulation 16, for example polyethylene. The tapes inside the rod form electrostatic partitions between the compartments 14.
The rod is made by excluding the covering 16 over the cruciform arrangement of the two metal tapes 15. The initially flat tapes are bent longitudinally at right angles along their median axis and are placed together along the bending line to form four branches at 90 each other immediately before extruding the covering. The edges of the strips can be flush with the surface of the covering at the periphery of the rod, as shown in dashed outline, to achieve continuity between the peripheral shield 13 and the interior tapes.
In a different embodiment (FIG. 3), a rod 30 made up of finned insulation material 31 which is extruded and externally metallized, the exterior metallization 32 being continuous from one fin to the next.
The pairs are assembled to the rod 10 as the rod moves past the point of coming together of the pairs. The pairs are deposited in the various compartments and the rod may be twisted into a spiral, for example in a rotating machine, with the pairs in place in the compartments. The twisted rod is represented by the broken lines around the outer periphery of the tips of the fins in FIG. 3 (similar to the way the broken lines around the conductor pairs represent the twisted pairs of conductors).
The shield 13 is a metal or combined plastics and metal tape. It is wrapped helically around the rod and the pairs as the pairs are placed in the compartments. The shield closes each V-shaped compartment. In this way each pair is individually shielded.
The protective sheath 5 is formed immediately after application of the shield 13 and is preferably extruded.
FIG. 2 shows a variant of the cable of the invention in which parts identical to those of the FIG. 1 cable are identified by the same reference numbers and are not described again. Only the differences are described below.
In FIG. 2, the individual pairs are shielded by the shield 13 previously described and a semiconductor polymer material which can be very weakly conductive at low electric fields and have a conductivity that increases with the field. The rod 20 also has radial fins 21. The material of the rod 20 can be of the type described in U.S. Pat. No. 5,416,155, which has a polymer matrix having an electrical conductivity less than 10.sup.-8 S/m but which increases as the electric field increases. The polymer matrix of this material includes a first thermoplastic or thermosetting insulative polymer and a second doped or undoped conjugate polymer having an electrical conductivity less than 10.sup.-4 S/m which increases as the electric field increases, representing between 5% and 70% by weight of said matrix. It may further contain a conductive charge, for example carbon black.
The rod 20 is preferably extruded but may instead be molded, injection molded or rolled. The fins of the rod 20 again constitute shielding partitions between the compartments, the effectiveness of which is proportional to the magnitude of the effect of the pairs on each other in the absence of the shielding thus obtained.
The cable of the invention is faster to manufacture and easier to manufacture on an industrial scale than circular cross-section cables with a shielding tape wrapped around each pair. Its impedance is very regular, which makes it compatible with transmission at high bit rates. It is also easy and quick to fit with a connector on site since to obtain access to the conductors of the pair all that is required is to remove the sheath from an appropriate length of the cable, to remove the peripheral shield over this same length and then to cut through the rod; this represents an important saving in time. The risks of damaging the conductors or disrupting the arrangement of the pairs when fitting the connector are also largely avoided.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US8429 *||Oct 14, 1851|| ||Improvement in water-wheels|
|US483285 *||May 6, 1892||Sep 27, 1892|| ||auilleaume|
|US661109 *||May 18, 1900||Nov 6, 1900||Albert Schmitz||Process of manufacturing pipes.|
|US1780564 *||Feb 20, 1924||Nov 4, 1930||American Brass Co||Electrical conductor|
|US3819443 *||Jan 15, 1973||Jun 25, 1974||Sun Chemical Corp||Method for making multifinned shielding tapes|
|US3911200 *||Aug 20, 1973||Oct 7, 1975||Sun Chemical Corp||Electrical cable housing assemblies|
|US4038487 *||Apr 5, 1976||Jul 26, 1977||Bell Telephone Laboratories, Incorporated||Shielded multipair cable|
|US5132488 *||Feb 21, 1991||Jul 21, 1992||Northern Telecom Limited||Electrical telecommunications cable|
|US5416155 *||Apr 1, 1992||May 16, 1995||Alcatel Cable||Material for semiconductive screening|
|DE3911978A1 *||Apr 12, 1989||Feb 15, 1990||Felten & Guilleaume Energie||Telecommunication cable - has copper conductors for high mechanical stresses to meet all safety conditions for power cables|
|FR684813A *|| ||Title not available|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US6248954 *||Feb 25, 1999||Jun 19, 2001||Cable Design Technologies, Inc.||Multi-pair data cable with configurable core filling and pair separation|
|US6259031 *||Aug 6, 1999||Jul 10, 2001||Krone Digital Communications||Cable with twisting filler|
|US6297454 *||Dec 2, 1999||Oct 2, 2001||Belden Wire & Cable Company||Cable separator spline|
|US6310295 *||Dec 3, 1999||Oct 30, 2001||Alcatel||Low-crosstalk data cable and method of manufacturing|
|US6342678 *||Mar 12, 1999||Jan 29, 2002||Nexans||Low-crosstalk flexible cable|
|US6365836 *||Jun 30, 1999||Apr 2, 2002||Nordx/Cdt, Inc.||Cross web for data grade cables|
|US6365837 *||Apr 11, 2001||Apr 2, 2002||James D. Mitchem||Non-tangling line|
|US6378283||May 25, 2000||Apr 30, 2002||Helix/Hitemp Cables, Inc.||Multiple conductor electrical cable with minimized crosstalk|
|US6462268||Apr 16, 2001||Oct 8, 2002||Krone, Inc.||Cable with twisting filler and shared sheath|
|US6506976 *||Sep 14, 1999||Jan 14, 2003||Avaya Technology Corp.||Electrical cable apparatus and method for making|
|US6570095||May 11, 2001||May 27, 2003||Cable Design Technologies, Inc.||Multi-pair data cable with configurable core filling and pair separation|
|US6596944 *||Mar 21, 2000||Jul 22, 2003||Cable Design Technologies, Inc.||Enhanced data cable with cross-twist cabled core profile|
|US6624359||Dec 14, 2001||Sep 23, 2003||Neptco Incorporated||Multifolded composite tape for use in cable manufacture and methods for making same|
|US6639152||Aug 25, 2001||Oct 28, 2003||Cable Components Group, Llc||High performance support-separator for communications cable|
|US6787697 *||Jan 16, 2001||Sep 7, 2004||Belden Wire & Cable Company||Cable channel filler with imbedded shield and cable containing the same|
|US6812408||May 28, 2003||Nov 2, 2004||Cable Design Technologies, Inc.||Multi-pair data cable with configurable core filling and pair separation|
|US6818832 *||Apr 22, 2002||Nov 16, 2004||Commscope Solutions Properties, Llc||Network cable with elliptical crossweb fin structure|
|US6826338 *||Feb 19, 2002||Nov 30, 2004||Asahi Glass Company, Limited||Optical fiber cable having a partitioning spacer|
|US6855889||Aug 13, 2001||Feb 15, 2005||Belden Wire & Cable Company||Cable separator spline|
|US6888070 *||Oct 16, 2000||May 3, 2005||Raydex/Cdt Limited||Cables including fillers|
|US6974913||Jun 25, 2003||Dec 13, 2005||Neptco Incorporated||Multifolded composite tape for use in cable manufacture and methods for making same|
|US6998537||Jan 3, 2003||Feb 14, 2006||Belden Cdt Networking, Inc.||Multi-pair data cable with configurable core filling and pair separation|
|US7015397||May 27, 2003||Mar 21, 2006||Belden Cdt Networking, Inc.||Multi-pair communication cable using different twist lay lengths and pair proximity control|
|US7115815||Dec 26, 2003||Oct 3, 2006||Adc Telecommunications, Inc.||Cable utilizing varying lay length mechanisms to minimize alien crosstalk|
|US7135641||Aug 4, 2005||Nov 14, 2006||Belden Technologies, Inc.||Data cable with cross-twist cabled core profile|
|US7145080||Nov 8, 2005||Dec 5, 2006||Hitachi Cable Manchester, Inc.||Off-set communications cable|
|US7154043||Nov 10, 2003||Dec 26, 2006||Belden Technologies, Inc.||Data cable with cross-twist cabled core profile|
|US7173189 *||Nov 4, 2005||Feb 6, 2007||Adc Telecommunications, Inc.||Concentric multi-pair cable with filler|
|US7173191||Apr 1, 2005||Feb 6, 2007||Raydex/Cdt Ltd.||Cables including fillers|
|US7179999||Feb 13, 2006||Feb 20, 2007||Belden Technologies, Inc.||Multi-pair data cable with configurable core filling and pair separation|
|US7196271||Mar 3, 2003||Mar 27, 2007||Belden Cdt (Canada) Inc.||Twisted pair cable with cable separator|
|US7214882 *||Feb 26, 2002||May 8, 2007||Prysmian Cavi E Sistemi Energia S.R.L.||Communications cable, method and plant for manufacturing the same|
|US7214884||Dec 26, 2003||May 8, 2007||Adc Incorporated||Cable with offset filler|
|US7220918||Mar 24, 2005||May 22, 2007||Adc Incorporated||Cable with offset filler|
|US7220919||Mar 24, 2005||May 22, 2007||Adc Incorporated||Cable with offset filler|
|US7241953 *||Jun 13, 2003||Jul 10, 2007||Cable Components Group, Llc.||Support-separators for high performance communications cable with optional hollow tubes for; blown optical fiber, coaxial, and/or twisted pair conductors|
|US7271342||Dec 22, 2005||Sep 18, 2007||Adc Telecommunications, Inc.||Cable with twisted pair centering arrangement|
|US7271344||Mar 9, 2006||Sep 18, 2007||Adc Telecommunications, Inc.||Multi-pair cable with channeled jackets|
|US7272284||Jan 29, 2004||Sep 18, 2007||Honeywell International Inc.||Bundled cables and method of making the same|
|US7329815||Jul 19, 2005||Feb 12, 2008||Adc Incorporated||Cable with offset filler|
|US7339116 *||Jan 18, 2001||Mar 4, 2008||Belden Technology, Inc.||High performance data cable|
|US7375284||Jun 21, 2006||May 20, 2008||Adc Telecommunications, Inc.||Multi-pair cable with varying lay length|
|US7405360||Feb 9, 2007||Jul 29, 2008||Belden Technologies, Inc.||Data cable with cross-twist cabled core profile|
|US7411131||Jun 22, 2006||Aug 12, 2008||Adc Telecommunications, Inc.||Twisted pairs cable with shielding arrangement|
|US7432447 *||Mar 5, 2007||Oct 7, 2008||Cable Components Group, Llc||Support separators for high performance communications cable with optional hollow tubes for; blown optical fiber, coaxial, and/or twisted pair conductors|
|US7449638||Dec 8, 2006||Nov 11, 2008||Belden Technologies, Inc.||Twisted pair cable having improved crosstalk isolation|
|US7465879||Apr 21, 2006||Dec 16, 2008||Cable Components Group||Concentric-eccentric high performance, multi-media communications cables and cable support-separators utilizing roll-up designs|
|US7473849||Apr 21, 2006||Jan 6, 2009||Cable Components Group||Variable diameter conduit tubes for high performance, multi-media communication cable|
|US7473850||Apr 21, 2006||Jan 6, 2009||Cable Components Group||High performance, multi-media cable support-separator facilitating insertion and removal of conductive media|
|US7491888||Oct 23, 2006||Feb 17, 2009||Belden Technologies, Inc.||Data cable with cross-twist cabled core profile|
|US7495175||Jul 10, 2007||Feb 24, 2009||Honeywell International, Inc.||Bundled cables and method of making the same|
|US7498518||Dec 26, 2006||Mar 3, 2009||Adc Telecommunications, Inc.||Cable with offset filler|
|US7534964||Jun 20, 2008||May 19, 2009||Belden Technologies, Inc.||Data cable with cross-twist cabled core profile|
|US7550676||May 15, 2008||Jun 23, 2009||Adc Telecommunications, Inc.||Multi-pair cable with varying lay length|
|US7592550||Aug 10, 2007||Sep 22, 2009||Adc Telecommunications, Inc.||Cable with twisted pair centering arrangement|
|US7629536||Aug 10, 2007||Dec 8, 2009||Adc Telecommunications, Inc.||Multi-pair cable with channeled jackets|
|US7637776 *||May 17, 2007||Dec 29, 2009||Leviton Manufacturing Co., Inc.||Communication cabling with shielding separator system and method|
|US7663061 *||Oct 23, 2007||Feb 16, 2010||Belden Technologies, Inc.||High performance data cable|
|US7763805||Aug 12, 2008||Jul 27, 2010||Adc Telecommunications, Inc.||Twisted pairs cable with shielding arrangement|
|US7834271||Apr 28, 2009||Nov 16, 2010||Tyco Electronics Corporation||Cabling having shielding separators|
|US7875800||Feb 27, 2009||Jan 25, 2011||Adc Telecommunications, Inc.||Cable with offset filler|
|US7897875||Nov 19, 2008||Mar 1, 2011||Belden Inc.||Separator spline and cables using same|
|US7977575 *||Dec 23, 2009||Jul 12, 2011||Belden Inc.||High performance data cable|
|US7999184||Mar 19, 2009||Aug 16, 2011||Commscope, Inc. Of North Carolina||Separator tape for twisted pair in LAN cable|
|US8030571||Jun 30, 2010||Oct 4, 2011||Belden Inc.||Web for separating conductors in a communication cable|
|US8198536||Oct 7, 2008||Jun 12, 2012||Belden Inc.||Twisted pair cable having improved crosstalk isolation|
|US8313346 *||Dec 22, 2009||Nov 20, 2012||Leviton Manufacturing Co., Inc.||Communication cabling with shielding separator and discontinuous cable shield|
|US8319104||Feb 12, 2010||Nov 27, 2012||General Cable Technologies Corporation||Separator for communication cable with shaped ends|
|US8375694||Jan 17, 2011||Feb 19, 2013||Adc Telecommunications, Inc.||Cable with offset filler|
|US8425260||May 6, 2010||Apr 23, 2013||Leviton Manufacturing Co., Inc.||High speed data communications cable having reduced susceptibility to modal alien crosstalk|
|US8426732 *||Feb 12, 2010||Apr 23, 2013||Superior Essex Communications Lp||Communication cable with improved member for positioning signal conductors|
|US8497428 *||Sep 8, 2011||Jul 30, 2013||Belden Inc.||High performance data cable|
|US8536455 *||Jun 30, 2011||Sep 17, 2013||Belden Inc.||High performance data cable|
|US8559778||Apr 22, 2010||Oct 15, 2013||Corning Cable Systems Llc||High density multifiber interconnect cable|
|US20100096179 *||Dec 22, 2009||Apr 22, 2010||Leviton Manufacturing Co., Inc.||Communication cabling with shielding separator and discontinuous cable shield|
|US20110253419 *||Jun 30, 2011||Oct 20, 2011||Belden Inc.||High performance data cable|
|US20110315443 *||Sep 8, 2011||Dec 29, 2011||Belden Inc.||High performance data cable|
|EP1117103A2 *||Jan 12, 2001||Jul 18, 2001||Avaya Technology Corp.||Electrical cable having improved flame retardancy and reduced crosstalk and method for making|
|EP1139350A2 *||Feb 14, 2001||Oct 4, 2001||Kerpenwerk GmbH & Co||Cable and manufacturing method of a cable|
|WO2001029849A1 *||Oct 16, 2000||Apr 26, 2001||Stephen John Prescott||Cables including fillers|
|WO2001054139A1 *||Dec 1, 2000||Jul 26, 2001||Belden Wire And Cable Company||A cable channel filler and cable containing the same|
|WO2001054142A1 *||Jan 16, 2001||Jul 26, 2001||Belden Wire & Cable Co||A cable channel filler with imbedded shield and cable containing the same|
|WO2007137146A2 *||May 17, 2007||Nov 29, 2007||Leviton Manufacturing Co||Communication cabling with shielding separator system and method|
|WO2013009570A1 *||Jul 5, 2012||Jan 17, 2013||General Cable Technologies Corporation||Shielding for cable components and method|
|Mar 10, 2011||FPAY||Fee payment|
Year of fee payment: 12
|Mar 8, 2007||FPAY||Fee payment|
Year of fee payment: 8
|Feb 20, 2003||FPAY||Fee payment|
Year of fee payment: 4
|Jun 25, 2001||AS||Assignment|
Owner name: NEXANS, FRANCE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ALCATEL N.V.;REEL/FRAME:011911/0039
Effective date: 20010308
Owner name: NEXANS 16, RUE DE MONCEAU 75008 PARIS FRANCE
Owner name: NEXANS 16, RUE DE MONCEAU75008 PARIS, (1) /AE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ALCATEL N.V. /AR;REEL/FRAME:011911/0039
|Oct 2, 2000||AS||Assignment|
Owner name: ALCATEL CABLE FRANCE, FRANCE
Free format text: MERGER;ASSIGNOR:FILOTEX;REEL/FRAME:011177/0556
Effective date: 19971014
Owner name: ALCATEL, FRANCE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FRANCE, ALCATEL CABLE;REEL/FRAME:011177/0562
Effective date: 20000901
Owner name: ALCATEL 54 RUE LA BOETIE 75008 PARIS FRANCE
Owner name: ALCATEL CABLE FRANCE 30, RUE PIERRE BEREGOVOY CLIC
|Oct 28, 1996||AS||Assignment|
Owner name: FILOTEX, FRANCE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:PRUDHON, DANIEL;REEL/FRAME:008242/0813
Effective date: 19960927